Published on February 28, 2010
Slide 1: CELL PHONE DETECTOR GROUP MEMBERS : GROUP MEMBERS DIVYA.U 11807106026 JAYASHREE.N 11807106036 MANJULA.P 11807106049 PREETHI.V.S 11807106062 Project Co-ordinator Guided by Mrs.K.S.RANI M.E. Mrs.C.SURVENIKA M.E. ABSTRACT : ABSTRACT When the cell phone detector signal is detected by C3, the output of IC1 becomes high and low alternately according to the frequency of the signal as indicated by LED1. This triggers monostable timer IC2 through capacitor C7. Capacitor C6 maintains the base bias of transistor T1 for fast switching action. The low-value timing components R6 and C9 produce very short time delay to avoid audio nuisance. The moment the bug detects RF transmission signal from an activated mobile phone, it starts sounding a beep alarm and the LED blinks. The alarm continues until the signal transmission ceases. INTRODUTION : INTRODUTION This handy cell phone detector, pocket-size mobile transmission detector or sniffer can sense the presence of an activated mobile cell phone from a distance of one and-a-half meters. So it can be used to prevent use of mobile phones in examination halls, confidential rooms, etc. It is also useful for detecting the use of mobile phone for spying and unauthorized video transmission. The circuit can detect both the incoming and outgoing calls, SMS and video transmission even if the mobile phone is kept in the silent mode. BLOCK DIAGRAM : BLOCK DIAGRAM Slide 6: CIRCUIT DIAGRAM ANTENNA : ANTENNA The size and shape of the antenna and the way it's constructed determine the gain and directivity of the antenna. The antenna transmits and receives electromagnetic signals. When gain increases the amount of desired signal energy that can be captured Increase but the amount of environmental noise and interferences that's captured increases by the same amount. IC CA3130 : IC CA3130 Op-amp IC CA3130 (IC1) is used in the circuit as a current-to-voltage converter It is a CMOS version using gate-protected p-channel MOSFET transistors in the input to provide very high input impedance, very low input current and very high speed of performance The output CMOS transistor is capable of swinging the output within 10mv of either supply voltage terminals NE555 : NE555 The NE555 is a highly stable controller capable of producing accurate timing pulses. With a monostable operation,time delay is controlled by one external resistor and one capacitor. With an astable operation,frequency and duty cycle are accurately controlled by two external resistors and one capacitor PIEZO-EIECTRIC BUFFER : PIEZO-EIECTRIC BUFFER A piezoelectric sensor is a device that uses the piezoelectric effect to measure pressure, acceleration, strain or force by converting them to an electrical signal. A piezoelectric disk generates a voltage when deformed They are used for quality assurance, process control and for research and development in many different industries. LED : LED An electronic device that lights up when electricity is passed through it. LEDs are usually red. They are good for displaying images because they can be relatively small. The moment the bug detects RF transmission signal from an activated mobile phone, it starts sounding a beep alarm and the LED blinks. LED’s contain an integrated multivibrator circuit inside which causes the LED to flash with a typical time period. FUTURE ENHANCEMENT : FUTURE ENHANCEMENT This project for military and civil defence for mobile radiation detection. Used for spying the unauthorised video transmission in mobile phones. Used to prevent the usage of mobile phones in examination and seminar halls. The signals emitted by mobile phones can interfere with some electronic equipment inside the hospital. This could have fatal consequences.so we use this project to detect the usage of mobile phones in the above places. conclusion : conclusion By choosing this project, we have not only learnt the technology of detection of cell phones during the fraudulent usage, but also got interested to enrich our knowledge in the field of electronics.